Tris (hydroxymethyl) aminomethane theophylline acetate

ABSTRACT

THE PRESENT INVENTION RELATES TO COMPOSITIONS OF TRIS (HYDROXYMETHYL) AMINOMETHANE WITH MONOCARBOXYLIC AMINATED ORGANIC OACIDS SUCH AS THEOPHYLLINE-ACETIC ACID, THIOCTIC ACID, OROTIC ACID AND PANGAMIC ACID, THE METHOD OF MANUFACTURING THE SAME, AND THE METHOD OF TREATING ACIDOSIS BY ADMINSTRATION OF THE SAME.

United States Patent Oflice 3,562,273 Patented Feb. 9, 1971 Int. or.(Jim 57/52 U.S. Cl. 260-253 1 Claim ABSTRACT OF THE DISCLOSURE Thepresent invention relates to compositions of tris (hydroxymethyl)aminomethane with monocarboxylic aminated organic acids such astheophylline-acetic acid, thioctic acid, orotic acid and pangamic acid,the method of manufacturing the same, and the method of treatingacidosis by administration of the same.

The present invention concerns new compounds of antiacidotic action suchas the derivatives of tris (hydroxymethyl) amiuomethane, of importanttherapeutic applications.

Constant blood pH is essential for the development of vital processes ofthe human organism. However, the acidosis produced either by abnormalaccumulation in blood of ketone groups originating from the abnormalcatabolism of fatty. acids together with a deficiency in the metabolismof carbohydrates, either by failure in the mechanism regulating theblood and extra-blood pH.

In the first type of acidosis, the treatment can be directed to increasethe pH and the alkali reserve, to promote the whole metabolism of theketone bodies, or both, simultaneously.

In the second case, the treatment must be directed to increase thealkali reserve and to activate the extra-blood regulator mechanisms.

In general, the treatments used up to now were directed to normalize thepH by increasing the alkali reserve.

For instance, use was made of sodium bicarbonate which acts exclusivelyas a blood butter, but it shows the disadvantage of beingcontraindicated in the acidosis of respiratory or renal nature and beingdevoid of intracellular buffer action.

In 1959, Nahas introduced the organic amines, among whichby its efficacyand non-toxicitythe tris (hydroxymethyl) aminomethane or THAM, which notonly acts as a plasmatic buffer but also as an intracellular buffer.

However, the THAM shows some disadvantages in relation to itsadministration since its solutions are too alkaline and may provokedigestive troubles. On the other hand, it is not active against thecauses of the acidosis.

To correct such disadvantages in the treatment of acidosis we havedirected our investigation towards the synthesis of THAM derivativeshaving more effective therapeutic properties and being better tolerated.

In this way we have synthesized a series of THAM derivatives withorganic acids acting on acidosis. The mentioned compounds not onlyreestablish the pH but they are also active against the causes producingthe changes, and they differentiate from the antiacidotic substancesknown so far.

The method of obtaining these compounds is essentially based on thedirect reaction of the respective acid with tris (hydroxymethyl)aminomethane, either in the fusion state or in a suitable solvent.

These compounds can also be obtained by reacting the salts of thecomponents by means of double replacement in a solvent that is suitablein each particular case.

The invention is illustrated, by the following examples:

EXAMPLE 1 200 g. of theophylline and 500 cc. of water are heated toebullition and added to g. of chloroacetic acid and small portions ofsodium hydroxide 30% without discontinuing agitation and heatingstrongly for 10 minutes. Then keep slow ebullition for another 30minutes.

The solution is then cooled in a drier, then filtered, the resultingcrystals are washed with slightly acidified water and, finally,desiccated. The crystals thus obtained correspond to theophylline aceticacid.

100 g. of theophylline acetic acid perfectly dried are pulverized with50.9 g. of tris (hydroxymethyl) amino methane in a mortar until ahomogenous mixture is obtained. The mixture is immediately transferredto a steel container in oil bath and heated to 150l75 C.

The mixture is constantly and vigorously agitated until a limpid liquidis obtained which is dropped, still scalding, into steel trays and,finally, is subjected to vacuum desiccation to preserve from moisture.

The desiccated product must be manipulated rapidly and in a very drymedium as it is very hygroscopic. In this way are obtained some 145 g.of tris (hydroxymethyl) aminomethane theophylline acetate.

EXAMPLE 2 26.0 g. of sodium theophylline acetate are dissolved in thesmallest possible quantity of water, to which 15.8 g. of tris(hydroxymethyl) aminomethane hydrochloride is added.

Ebullition is maintained for 30 minutes; then 200 cc. of warm alcohol 96are added, and the hot solution is filtered to separate the NaCl thusformed. The resulting solution is vacuum evaporated until a pasty massof crystals is detached and then treated with absolute alcohol; theevaporation to dryness is repeated to eliminate the remaining water.

The efiiciency is 88%.

The product thus obtained has been identified as the tris(hydroxymethyl) aminomethane theophylline-acetate of molecular weight359.3, empirical formula 13 21 5 'z and structural formula:

o int-00011 N H C-N F I I HOHzC-OCH2OH 0 N HzOH White powder,hygroscopic, melting at C., very soluble in water and warm alcohol,sparingly soluble in 3 cold alcohol, insoluble in chloroform, acetone,benzene and ether. In 0.05 M solution it has a pH of 6.4. Its absorptionspectrum in ultraviolet in HCl 0.1 N shows a maximum at 272H1/1..

EXAMPLE 3 In a double opening 500 cc. matrass are placed 14.4 g. of tris(hydroxymethyl) aminomethane finely powdered and 125 cc. of absoluteethyl alcohol. The matrass is adjusted to a reflux cooler.

The mixture is heated in water-bath until the tris(hydroxyrnethyl)aminomethane is dissolved. In the free end of the matrass is adjusted aseparatory funnel containing a solution of 25 g. of thioctic acid in 125cc. alcohol.

This solution is slowly dropped in the matrass for 30 minutes alwaysmaintaining the matrass contents in ebullition. Then the ebullition ismaintained for another 10 minutes to complete the reaction.

The solution being still hot, it is carefully vacuum concentrated toavoid sudden elimination of the alcohol. It is cooled in therefrigerator for 3 to 4 hours, with occasional agitation to obtaincrystallization.

The mixture is vacuum filtered and dried in the drying chamber at 60 C.for 1 hour.

The product is re-crystallized in alcohol at the rate of 4 cc.alcohol/g, then the crystals are washed with anhydrous ether and driedin the drying chamber at 60 C. A tris (hydroxymethyl) aminoethanethioctate, crystalline yellowish powder of 120 C. melting point, isobtained.

The efiiciency is 87%.

EXAMPLE 4 15.8 g. of tris (hydroxymethyl) aminomethane hydrochloride aredissolved in the smallest possible quantity of water and 22.8 g. ofsodium thioctate are previously added, dissolved in the smallestpossible quantity of water.

The resulting solution is maintained in ebullition for 30 minutes andone part of the solvent is allowed to evaporate. Then it is allowed tocool, 200 cc. of alcohol are added and the mixture is heated again. Thesolution, still hot, is immediately filtered to separate the sodiumchloride thus formed. The solution is slowly cooled in the refrigeratorand the product becomes crystallized.

The product is vacuum filtered and dried, then recrystallized in alcoholas in Example 3. The efiiciency is in the range of 80% but the motherwaters of crystallization can be used for a new obtention.

The product obtained, the tris (hydroxymethyl) aminomethane thioctate,has the empirical formula:

and it corresponds to the following structural formula:

CH2OH The molecular weight is 327.5 and its melting point is 120 C.

It is a yellow crystalline powder, very soluble in water and in hotalcohol. It is sparingly soluble in cold alcohol and in warm acetone. Itis insoluble in chloroform, benzene and ether. In 0.1 M aqueous solutionit has a pH of 6.5. Its ultraviolet spectrum shows a maximum absorptionof 335m in ethanol.

EXAMPLE 5 4 The product thus obtained is a microcrystalline powder,soluble in water and in alcohol and insoluble in ether.

EXAMPLE 6 Small amounts of water are added to 15 g. of sodium pangamateuntil complete dissolution.

On the other hand, 7.6 g. of tris (hydroxymethyl) aminomethanehydrochloride are dissolved in the smallest possible amount of water.The solutions are mixed and heated to ebullition.

96 alcohol is added to the necessary amount until the sodium chloridestarts becoming insoluble, then 10 cc. of 96 alcohol is added.

The solution is filtered and the residue is washed with 96 alcohol.

Both filtrates are joined. The solution is evaporated to dryness withvacuum aid.

Efiiciency is in the range of 96% A series of toxicologic, pharmacologicand clinical experiences have been carried out with the new compounds.

The LD 50 of tris (hydroxymethyl) aminomethane theophylline acetate inalbino mice by oral route is 4.05:0.174 g./kg. and 2.45 i0.145 g./kg. byintravenous route.

The LD 50 of tris (hydroxymethyl) aminomethane thioctate in mice is506:4.71 mg. by oral route, 126.4: 5.76 mg./kg. by intravenous route and27815.69 mg./ kg. by intraperitoneal route.

This compound has also been experimented in rats. The LD 50 is 1600:168mg./kg. by oral route, 345.2: 27.1 mg./kg. by intravenous route and365:255 mg./ kg. by intraperitoneal route.

All results are expressed according to the Reed-Muench method.

The buffer capacity of these compounds has been verified in dogsanesthetized with pentothal with acute experimental acidosis induced byiv. injection of a solution of phosphates, ammonium chloride, lacticacid, etc. up to a pH of 7.2.

When the product is administered by intravenous route the pH return tonormal values and the reserve expressed in bicarbonate is recuperated.

The study of the results of the administration of 50 mg./kg. of tris(hydroxymethyl) aminomethane thioctate to cats weighing 2 to 3 kg.showed no changes in blood pressure nor modification of the respiratoryrecording. The electrocardiogram was neither modified during or afteradministration.

The tris (hydroxymethyl) aminomethane theophylline. acetate can beconsidered, by its characteristics, as a complete antiacidotic productsince it acts not only on the blood factors that regulate the pH butalso on the cellular pulmonary and renal factors.

In acidosis of intracellular origin, the new compound acts as a protonacceptor neutralizing the intracellular hydrogen ions. In respiratoryacidosis, the depressant action of tris (hydroxymethyl) aminomethane onthe respiratory centers is counter acted by the stimulant action exertedby the theophylline on them. In renal acidosis, there is a synergismbetween the diuretic action of osmotic and tubular type of the tris(hydroxymethyl) aminomethane with that of glomerular type of thetheophylline.

Clinically, the tris (hydroxymethyl) aminomethane theophylline-acetateis indicated in all types of toxic, respiratory or metabolic acidosis oftissular, pulmonary, plasmatic, or renal origin. Also in intoxicationsof medicamental origin produced by barbiturates, salicylic derivativesand the like, in which it facilitates the quick elimination of the toxicsubstances by renal route.

As it has a slightly alkaline pH, the new compound can be administered,unlike the tris (hydroxymethyl) aminomethane, by oral route withoutproducing digestive troubles, and by intravenous route without provokingirritations.

6 Clinically, excellent results have been obtained with References Citedthe tris (hydroxymethyl) aminomethane thioctate, oro- UNITED STATESPATENTS tate and pangamate by its buffer and eumetabolic action inacidosis of metabolic or toxic type related with troux 3: bles of theliver function or of the metabolism of glu- 5 v3098854 6/1963 Klosa 26O253 cides. Likewise, in acidoketosis by fever, vomiting, ketonuria,dehydratations, denutrition, alcoholism, diabetic ALEX MAZEL, PrimaryExaminer acidosis, post-anesthetic acidosis, etc. TIGHE, AssistantExaminer We claim: 1. A composition of matter tris (hydroxymethyl) maminomethane theophylline acetate. 260-460, 327, 482; 424-251, 253, 277,311

